[JEXL-367] Named function and fat-arrow (=>) lambda syntax

• Type: Wish
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.2.1
• Fix Version/s: 3.3
• Assignee: Henri Biestro
• Reporter: Hussachai Puripunpinyo
• Created: 26/Apr/22 18:32
• Updated: 27/Mar/23 10:59
• Resolved: 21/May/22 10:04

Description

The JEXL code surprisingly looks a lot like Javascript. I think this change is a good transition for folks to update the code, and it's pretty fine if they can tolerate using the deprecate syntax and don't mind seeing a warning log pop up every time. 

I'd like to propose supporting => and deprecate ->.
The reasons are

• JavaScript becomes very popular and many people are familiar with it.
• JEXL is more like for a quick short script. In many scenarios, the target audiences are not a programer. They often mistake a language as a JavaScript (from my experience).
• JEXL syntax already looks a lot like JavaScript
  • var for variable declaration (Java added in Java 10, but JavaScript supports this from the beginning)
  • The function keyword
  • Implicit type coercion
  • Ternary operator

The proposed change.

• Support => in addition to ->
• Deprecate -> and show a warning log when it's used.

Issue Links

• incorporates: JEXL-377 Add support for javascript style function definition
• links to: GitHub Pull Request #96